Railway system with noise suppression means



Oct. 19, 1965 R. L. LICH RAILWAY SYSTEM WITH NOISE SUPPRESSION MEANS Filed Jan. 25, 1964 H mm 5 T E N M mm mm {m H A m RM V! B \m t/ l mij HHUUm l l l f l i lw H H I IUWI I I HH I I U I I F H HI I HFHH HHH m m m I ILI I I ll lllll ll II l| ll m RIIUIIII llllllllll ll l lllllll II HI! 1| Q w Eh I Q \v\ v x Q. I a q w ml? OE United States Patent Office Patented Oct. 19, 1965 3,212,453 RAILWAY SYSTEM WITH NOISE SUPPRESSION MEANS Richard L. Lich, St. Louis, Mo., assignor to General Steel Industries, Inc., Granite City, 11]., a corporation of Delaware Filed Jan. 23, 1964, Ser. No. 339,649 7 Claims. (Cl. 104-124) The invention relates to railways and consists particularly in a railway system having means for suppressing the noise of railway operation.

The major objection to the use of elevated railways for urban rapid transit is the high noise level of the conventional type of elevated railway, in which the rails are usually mounted directly, or by means of steel tie plates, on wooden ties resting directly on steel girders supported by steel posts. The major portion of the objectionable noise is caused by the engagement of the steel car wheels with the steel rails and it reverberates through the elevated structure and is transmitted therefrom through the air.

It is accordingly a main object of the invention to make elevated railways more suitable for urban rapid transit service by reducing their noise level.

It is a further object to provide an elevated railway system in which the transmission of operating noises will be reduced to a minimum.

The foregoing and additional more detailed objects and advantages of the invention will be evident from the following description and the accompanying drawings, in which:

FIG. 1 is a partial side elevational view of an elevated railway and car thereof embodying the invention.

FIG. 2 is an enlarged transverse vertical sectional view along line 22 of FIG. 1.

The roadbed comprises precast concrete beams 1 of generally cruciform cross section supported above the ground at spaced intervals on concrete columns 3. The main portion of beams 1 is of rectangular cross section and is provided with outwardly projecting shelves 5 at each side at a slightly lower level than the top of the beam. On the upper surfaces of shelves 5 are mounted, at closely spaced intervals, sandwiches 7, each comprising a pad of resilient material, such as rubber, between metal plates, and the track rails 9 are mounted on the tops of sandwiches 7, the tops of rails 9 being substantially flush with the top of the central portion of beam 1 thereby rendering the provision of separate guard rails unnecessary.

A car comprising a body 6, trucks 8 with flanged wheels 10 is guidably supported on the track by the engagement of wheels 10 with rails 9.

It will be evident that the transmission of vibrations and sounds of car operation from rails 9 to beam 1 will be minimized by the sound insulating and cushioning effect of rubber sandwiches 7. For additionally preventing any transmission of such sounds from the roadbed, the outer extremities of shelves 5 are provided with brackets 11 which are spaced apart longitudinally of the beam and support at their outer extremities longitudinally elongated upright shields 13. Shields 13 are preferably of extruded thermoplastic material or other material having less sound conductivity and higher sound absorption characteristics than metal and for rigidity are formed with inwardly turned upper and lower flange portions 15. The upper edges of shields 13 extend well above the top of the rail and their lower edges extend substantially an equal distance below the bottom of the rail and preferably below the bottoms of shelves 5, thus preventing direct lateral transmission of the rail noises, and the spacing of the shields from the rail supporting shelves 5 of beams 1 eliminates the cavity resonance which would occur if the shields were secured directly to the outer margins of shelves 5.

To further insure against the transmission of rail noises, the car body 6 is provided at its sides with depending skirts 19 also preferably of extruded thermoplastic material of low sound conductivity which extend to a substantially lower level than the upper margins of the beammounted shields 13 and are spaced slightly outwardly therefrom so as to cooperate with shields 13 to form a battle blocking the direct lateral transmission not only of rail noises but also of other operating noises such as those produced by traction motors, driving gears, air compressors and the like.

During operation of a railway system embodying this invention, the solid beam will block the downward transmission of noises usually transmitted in the openwork construction of conventional elevated railway structures and the rubber mounting of the rails will, to a large extent, isolate the operatnig noises from the beams. The overlapping relation between the car-mounted skirts 19, beammounted shields 13 and the beams themselves will block the airborne transmission of noises created by the wheelrail engagement, and driving gear, traction motor, suspension and compressor noises outwardly from the railway. The details of the structure may be varied substantially without departing from the spirit of the invention and the exclusive use of those modifications coming within the scope of the claims is contemplated.

What is claimed is:

1. A railway system comprising spaced rails, means supporting said rails, upright continuous shields supported from said rail-supporting means at each side thereof outwardly of said rails, and a car carried by said rails and having a depending skirt at each side spaced outwardly from said shields and extending below the tops thereof.

2. A railway system according to claim 1 in which said shields and skirts are of material of low sound conductivity.

3. A railway system according to claim 1 in which said shields are spaced outwardly from said rail supporting means.

4. A railway system according to claim 3 in which said rail-supporting means is an elevated beam, and bracket means spaced apart lengthwise thereof forms the supports of said shields therefrom.

5. A railway system comprising spaced rails, a beam supporting said rails above the ground, brackets mounted on said beam and extending laterally outwardly therefrom, said brackets being spaced apart longitudinally of said beam, continuous upright shields mounted on said brackets in spaced relation with said beam at both sides thereof and extending upwardly and downwardly to levels substantially higher and lower than said rails, and a car carried by said rails and having a substantially upright depending skirt at each side spaced outwardly from said shields and extending downwardly below the tops thereof.

6. A railway system according to claim 5 in which said beam is of cruciform cross-section having a substantially rectangular body and horizontally aligned shelves projecting outwardly from the sides thereof, said rails being supported on the upper surfaces of said shelves and said brackets being fastened to the sides of said shelves, said shields terminating below the bottom surface of said shelves.

7. A railway system according to claim 5 in which pads of resilient material are interposed between said rails and the rail-supporting surfaces of said beam.

No references cited.

MILTON BUCHLER, Primary Examiner. 

1. A RAILWAY SYSTEM COMPRISING SPACED RAILS, MEANS SUPPORTING SAID RAILS, UPRIGHT CONTINUOUS SHIELDS SUPPORTED FROM SAID RAIL-SUPPORTING MEANS AT EACH SIDE THEREOF OUTWARDLY OF SAID RAILS, AND A CAR CARRIED BY SAID RAILS AND HAVING A DEPENDING SKIRT AT EACH SIDE SPACED OUTWARDLY FROM SAID SHIELDS AND EXTENDING BELOW THE TOPS THEREOF. 